This was previously answered by Sandor Farkas who said Tier 3 has a hard connection limit of two accounts. As of the change, Tier 3 can connect two Google accounts (it used to be one Google + one Meta), and additional account connections become available starting with Tier 4. You can find that answer here: https://appsumo.com/products/connexify/questions/limitations-1405855/

I think Tier 3 should include at least three accounts to cover basic usage (Google, Meta, and TikTok). Since you’ve recently added TikTok, are you planning to adjust the Tier 3 plan? Otherwise, Tier 3 wouldn’t be enough, while Tier 4 is very expensive for an agency that onboards few clients